Fix clock showing incorrect time Windows and Linux Dual Boot If you have a computer where a Linux OS is dual-booted with Windows, you will notice that, sometimes you reboot from Linux to Window, the clock time is displaying incorrectly in Windows. Even some Linux systems may show the incorrect time if you are returning from Windows. This Linux behavior can easily be changed though, so just login to your Linux system. NOTE: This is just one way to correct this and works with Ubuntu and Mint. Other Linux distros store the information in other locations you will need to refer to their help sections. You need to edit the file rcS located in the /etc/default/ directory and set UTC=no. You can do this by using any text editor or use following method if you have gedit installed. Open Terminal (press Ctrl+Alt+T for quick access) and type the following command and hit Enter. NOTE: You can also copy and paste the commands in to the Terminal. Code: sudo cp /etc/default/rcS /etc/default/rcS_backup Type your password when it asks and hit Enter. NOTE: Remember when you type your password it will not show anything. This will create a back up of the file we will be editing. This way should you need to revert back to the original file you can. Code: sudo su root Type your password when it asks and hit Enter. This will give you root access. Now type the following command and hit Enter to open /etc/default/rcS file with gedit text editor. Code: gedit /etc/default/rcS NOTE: Yes the “S” is capitalized in “rcS” This will open the rcS file in gedit. Notice “UTC” is set to “yes” there. Replace “UTC=yes”with “UTC=no” and click Save on the toolbar. Close both gedit and Terminal. You are done. NOTE: You may need to change the time in the BIOS one last time prior to booting into Windows.